Process for the treatment of liquids



Feb. 27, 1934. s D G 1,948,948

PROCESS FOR THE TREATMENT OF LIQUIDS Original Filed Oct. 5, 1925 7 t 122 a i 5 55555:

INVENTOR l'V/Zl/A/V L5P/4L0/NQ.

' ATT RNEY Patented Feb. 27, 1934 "PRGCES'S "1 0R "THE "TREATMENT OFLIQUIDS William .=-L. Spalding, Westfield, N. ..l., iassignor 'toNational Aniline .& Chemical '00., Inc.,, New York,.N.Y., a.,corporationof New York original application octcber :5, i925, .smm :No.

i60,442,mow1Patent No. 12185392. :Divide'dzaml this application May '26,#1930. Serial ,No.

4 Claims.

This invention relates to a process for the treatment of liquids withammonia and, in its specific application, for the absorption of ammoniain water to produce aqua ammonia. This application is a division of mycopending application Serial No. 60,442, filed October 5, 1925, nowPatent 1,785,792.

The invention, as described more fully hereinafter, provides a liquidcirculatory system into which ammonia gas is vented from an autoclave.The ammonia enters the bottom of a riser pipe forming part of thesystem, and the buoyant effect resulting from the gas absorption, liquiddisplacement and heat in the gas, causes an upward flow through theriser. The pipe discharges into the bottom of a cooler, and this in turninto a tank. A downcomer pipe from the tank and connected to the bottomof the first pipe constitutes the return leg of the system. A reliefvalve for venting any non-condensed gases from the tank is provided, asthe system is preferably operated under pressure to give an increasedcapacity and efliciency of gas absorption.

In the drawing accompanying this specification, a

Fig. 1 is a diagrammatic showing of an apparatus embodying theinvention;

Fig. 2 is a detail showing the gas inlet into the circulatory system.The gases, generated in an autoclave l, or by any other suitable means,are led through a pipe 2 into a liquid circulating system. This systemcomprises a riser pipe 3 which is surrounded or connected at or near itsupper end to a cooler 4 and empties into the bottom of a tank 5. Adowncomer pipe 6 from the bottom of tank 5 connects with the lower endof the riser 3 and completes the system.

The tank 5 is provided with a relief valve 7, and a pipe 8 forconducting gases leads therefrom into a scrubber 9 which dischargesthrough a pipe 10. With the use of the relief valve, definite pressurescan be maintained on the circulatory system.

As difliculty may be experienced in starting operations, on account of areverse circulation down the pipe 3 caused by the water in the cooler 4being colder than in the pipe 6, a valve 11 is inserted in the lower endof the downcomer pipe Closing the valve 11 stops this initial flowdownward in the pipe 6 and, opening it again immediately after the gasis admitted permits the normal flow to start. However, a properlyconstructed gas inlet into the pipe 3 is found to be 5 suflicient tostart a flow upwardly in pipe 3. and

the valve 11 for this purpose becomes unnecessary. A drain 12 and valve13 are provided to remove the liquor at the end of the operation.

The gas may be admitted into the system in various ways, but aconstruction that is found satisfactory is shown in Fig. 2. A T 14connects the riser pipe 3 and the downcomer pipe 6, and a gas inlet tube15 forming a continuation of the pipe 2 extends into the T in thedirection of the riser 3. A plug 16 fits tightly about the tube and inthe T to hold the tube in place and prevent any leakage.

From the above description, the operation of the apparatus is believedevident. The ammonia enters the bottom of pipe 3 into the confinedunitary flowing stream of circulating water passing through pipes 6 and3 and is absorbed in the water. The unabsorbed gases act as liftingmeans, while the absorbed gases decrease the specific gravity of theliquid and also impart heat to it. These three factors impel an upwardoirculation into the cooler 4, where heat is abstracted and furtherabsorption may take place. The fluid mixture passes into the tank 5where the unabsorbed gases separate, and the excess 9 accumulation ofthese gases passes through the relief valve: The gases can be collectedand scrubbed, as shown, or otherwise disposed of. When the desireddegree of gas absorption has taken place, the liquid is drained from thesystem, and the system is refilled with fresh liquid, or with thesolution present in the scrubber 9. For this purpose a valve controlledpipe line 17 connects the scrubber and the tank 5.

By means of this construction an eflicient action is secured because ofthe intimate contact between the stream of water and the cocurrent fiowof ammonia. The use of pressure on the system proportionately increasesthe capacity and at the same time gives a more efllcient gas absorption.The cooler not only abstracts heat for promoting the thermalcirculation, but it also assists in the condensation-and consequentabsorption of the gases. A positive rapid circulation of a stream ofwater from and to the body of water in tank 5 without-the need of movingparts is insured by the combination of the three natural forces, thebuoyant "action of the gases, the decrease in specific gravity caused byabsorption and condensation, and the thermal circulation induced by heatin the gases, and the circulation is further accelerated by the ejectorconstruction adopted for the introduction of ammonia under pressure asthe velocity of the jet of ammonia is imparted to the liquid system. 110

I claim:

1. A process for the production of aqua ammonia which comprisesrecirculating an aqueous liquid in a cyclic path comprising a confinedflowing stream of said liquid and introducing ammonia into said flowingstream.

2. A process for the production of aqua ammonia which comprisesrecirculating an aqueous liquid in a cyclic path comprising a pool ofsaid liquid and a confined flowing stream of the same, introducingammonia into said stream, and cooling the thus treated liquid prior torecirculation for introduction thereinto of additional quantities ofammonia.

3. A process for the production of aqua ammonia which comprisesrecirculating an aqueous liquid in a cyclic path comprising a pool ofsaid liquid and a confined upwardly flowing stream of the same,introducing ammonia into said ammonia contained therein by absorption inWater, and utilizing the ammoniacal solution thus formed as an aqueousliquid for the absorption of ammonia in the aforesaid manner.

WILLIAM L. SPALDING.

